Lacrimal sac

Saccus lacrimalis

Sensory (eye & ear)OrgansHeadLeft and right

View left in 3D View right in 3D

What it is

A membranous pouch lying in the lacrimal fossa of the medial orbital wall, behind the medial canthal tendon; its upper end is closed and its lower end continues as the nasolacrimal duct.

Function

Collects tears from the canaliculi and passes them down to the nose.

Size

12-15 mm tall, 4-8 mm across.

Clinical note

Infection of a blocked sac (dacryocystitis) gives a tender swelling at the inner corner; dacryocystorhinostomy bypasses the blockage into the nose.